Komatsu HD785-7 Front Wheel Hub

[FRTCX001]

First time poster after finding this site this morning.

Run a small component rebuilder and we've had a front wheel hub returned after leaking on install (out of the telltale hose on the overflow tank).
On return we've tested the unit to verify the leak and also make sure we can test for the leak. Once stripped down we found that the Duo Cone hadn't seated correctly which is a problem but glad it's an obvious issue. We've replace the Duo with a new unit and reassembled everything, gone to test and found it leaking again.

Question: Is there another reason on these units that the oil could flow to the overflow tank or is it the Duo Cone again?

 

[Welder Dave]

Welcome to the forum. There's a ton of knowledge on here.

There's been discussion on the proper way to install Duo-Cone seals recently concerning a Cat dozer. If you click on the magnifying glass in the upper right of the page before you scroll down you could do a search under Duo-Cone seals. People to trust would be Tctractors, Nige, Cmark , Ozdozer and a few others who have lots of experience with them. I'm not at a computer so don't know how to post a link to the thread(s). If no one responds you could also start a new thread referencing Duo-Cone seals and leaking hubs.

 

[Nige]

First question. How exactly do you install the Duo-cones..?

I’m not familiar with the HD785 front hub. I assume it’s a bit like a Cat 777 but do you have a drawing showing a sectioned view of it.?

 

[Vetech63]

(out of the telltale hose on the overflow tank).

I have no idea what this is.

Once stripped down we found that the Duo Cone hadn't seated correctly which is a problem but glad it's an obvious issue.

Is this an OEM replacement or a will fit?

We've replace the Duo with a new unit and reassembled everything, gone to test and found it leaking again.

WAs it obvious again?

 

[Nige]

Does the HD785 have one or two Duo-Cone seals.? I'm assuming two and that it was the inner one that was leaking..?

Also when you pulled it apart the first time did you inspect/check whether or not the metal rings of the Duo Cone(s) were level and also did you check them for height compared to specification.?

Once stripped down we found that the Duo Cone hadn't seated correctly

Please can you explain in more detail exactly what you mean by that comment.